Conventionally, in a manufacturing process for a disposable worn article such as a pant-type disposable diaper having a front waistline portion, a rear waistline portion, and crotch portion having leg-hole openings formed therein, a continuous web processing device, which superimposes the front waistline portion and the rear waistline portion of the continuous web as a half-finished product, has been widely used. With such a continuous web processing device, generally, the continuous web is folded in two by superimposing the front waistline portion and the rear waistline portion on each other based on a part which turns into the crotch portion (for example, Patent Literature 1).